Device for automatic narrowing on both needle-beds of flat knitting machines

ABSTRACT

A DEVICE FOR AUTOMATIC NARROWING ON BOTH NEEDLE-BEDS OR FLAT KNITTING MACHINES WHICH CONSISTS IN REDUCING IN NUMBER OF THE KNITTING NEEDLES BY SELECTIVELY OPERATING THE FORWARD NEEDLES. THE NEEDLES SLIDE UP AND DOWN IN THEIR GROOVES BY PUSHING THEIR BUTTS IN THE APPROPRIATE DIRECTION. DURING THE OPERATION, ONLY THE TRANSFER NEEDLES   ARE ON THE FORWARD NEEDLE-BED AND ONLY NORMAL NEEDLES ARE ON THE REAR NEEDLE-BED. THIS DEVICE IS PARTICULARLY ADAPTED TO THE MANUFACTURE OF DOUBLE-JERSEY KNITTED FABRIC.

Sept. 28,1971 .3, ER OLE ETAL 3,608,335

'DEVICE FOR AUTOMATIC NARROWING ON BOTH NEEDLE-BEDS OF FLAT KNITTING MACHINES Filed April 10, 1969 l.l Sheets-Sheet 1 Fig. 1 v A a .I ll

INVENTORS Ercole BERARDI Giancorlo VERSETTI A TTIORNEY Sept. 28, 1971 ERCQLE EI'AL DEVICE mm AUTOMATIC NARROWING ON BOTH NEEDLE-BEDS OF FLAT KNITTING MACHINES ll Sheets-Sheet 2 Filed April 10, 1969 OOOQOQQ INVENTORS Ercole BERARDI Giancurlo VERSETTI ATTORNEY Sept. 28, 1971 ERCQLE ETAL 3,608,335

DEVICE FOR AUTOMATIC NARROWING ON BOTH NEEDLE-BEDS 0F FLAT KNITTING MACHINES Filed April 10, 1969 ll Sheets-Sheet 4 Fig.6

ATTORNEY Sept. 28, 197] ERCOLE ETAL 3,608,335

DEVICE FOR AUTOMATIC NARROWING ON BOTH NEEDLE-BEDS OF FLAT KNITTING MACHINES Filed April 10, 1969 11 Sheets-Sheet 5 mullumulll INVENTORS Ercolc BERARDI Giuncurlo VERSETTI A TTORNE Y Sept. 28, 1971 ERCQLE ETAL DEVICE FUR AUTOMATIC NARROWING on BOTH NEEDLE-BEDS OF FLAT KNITTING MACHINES 11 Sheets-Sheet 6 Filed April 10, 1969 INVENTORS Ercole BERARDI Gicncorlo VERSETTI ATTORNEY Sept. 28, 1971 ERCOLE ETAL 3,608,335

DEVICE FOR AUTOMATIC NARHOWING ON BOTH NEEDLE-BEDS OF FLAT KNITTING MACHINES Filed April I0, 1969 11 Sheets-Sheet 7 Fig.10

Fig. 12

INVENTORS Ercole BERARDI Gioncurlo VERSETTI A TTORNE Y Sept. 2B, 1971 ERCQLE EI'AL DEVICE FUR AUTOMATIC NARROWING ON BOTH NEEDLE-BEDS OF FLAT KNITTING MACHINES Filed April 10, 1969 11 Sheets-Sheet 8 INVENTORS Ercole BERARDI Ginncurlo VERSETTI ATTORNEY Sept. 28, 1971 ERCQLE ETAL 3,608,335

Y DEVICE FOR AUTOMATIC NAHROWING ON BOTH NEEDLE-BEDS 0F FLAT KNITTING MACHINES Filed April 10, 1969 ll Sheets-Sheet 9 INVENTURS Ercolc BERARDI Giancurlo VERSETTI ATTORNEY Sept. 28; 1971 B. ERCOLE ETAL DEVICE FOR AUTOMATIC NARROWING ON BOTH NEEDLE-BEDS OF FLAT KNITTING MACHINES 1 1 Sheets-Sheet 10 Filed April 10, 1969 INVENTORS Ercolu BERARDI Giuncorlo VERSETTI v ,4 TTORNEY Sept. 28, 1971 5,-E EI'AL DEVICE FUR AUTOMATIC NARROWING ON BOTH NEEDLE-BEDS 0F FLAT KNITTING MACHINES 11 Sheets-Sheet 11 Filed April 10, 1969 INVENTURS Ercole BERARDI Giuncurlo VERSETTI ATTORNEY Patented Sept. 28, 1971 3,608,335 DEVICE FOR AUTOMATIC NARROWING ON BOTH NEEDLE-BEDS OF FLAT KNITTING MACHINES Berardi Ercole, Lugo, and Versetti Giancarlo, Caravaggio, Italy, assignors to Societa responsabilita limitata Flmma, Faenza, Ravenna, Italy Filed Apr. 10, 1969, Ser. No. 814,944 Claims priority, application Italy, Apr. 12, 1968, 31,051/68 Int. Cl. D04b 7/10 US. C]. 66-70 4 Claims ABSTRACT OF THE DISCLOSURE A device for automatic narrowing on both needle-beds of fiat knitting machines which consists in reducing in number of the knitting needles by selectively operating the forward needles. The needles slide up and down in their grooves by pushing their butts in the appropriate direction. During the operation, only the transfer needles are on the forward needle-bed and only normal needles are on the rear needle-bed. This device is particularly adapted to the manufacture of double-jersey knitted fabric.

This invention relates to a device for automatic narrowing on both needle-beds of fiat knitting-machines, which facilitates the manufacture of double-jersey knitted fabric, with reduction, at will, in the number of needles knitting, that is to say, with the forward needles being selectively operable.

By double-jersey is normally understood a turn (i.e., a stroke and return-stroke of the carriage) of tubular knit, and a half-turn of single-knit (that is, in this case both needle-beds are used).

The device actuates both sets of needles exclusively by means of their butts. The needles are thus made to slide up and down in their grooves by pushing the said butts in the appropriate direction.

For operation with the said device the knitting-machine must have only transfer needles on the forward needlebed and only normal needles, or similar, on the rearneedle-bed.

Basically the device is composed of two symmetrical heads which are symmetrically mounted on a pivotal frame parallel to the guide-bars of the knitting-machine, which frame enables the aforesaid heads to be lowered onto the beds into the operative position and to be moved symmetrically and periodically by one, two or three needlespaces according to the predetermined program.

A punch, similar to that used by hosiers, is incorporated in each head and performs the narrowing, or transfer, automatically.

Each head comprises two mechanisms which we shall call mechanism A and mechanism B. Mechanism A acts on the needles of the rear needle-bed only and has the function of reducing the number of stitches by one, two or three needles. It actuates the needles by means of the butts, pushing them up to the level of the punch, causing the eyes of the punch to engage automatically with the hooks of the needles and then, still by means of the butts, returning the needles, together with the punch, to baseposition. In this phase of the process the punch picks up the stitches that were on the hooks and transfers them laterally to the adjacent needles (or, more precisely, to the hooks of the adjacent needles), thus performing the operation known as narrowing. In this final, transference phase the heads shift automatically and symmetrically to place the punch in correspondence with the needles that are to receive the stitches.

Mechanism B serves to raise and lower the transfer needles, which, as has been said, are arranged in the forward needle-bed, so as to enable a stitch to be trans ferred from a forward needle to a rear needle.

Mechanisms A and B are mechanically synchonized. Mechanism B operates before A and can be neutralized for narrowing on single-knit jersey fabrics.

It should be noted that, for the two heads to function, the latches of the needles of the rear bed must be triggered before the heads themselves come into operation. This is achieved by modifying the triangles of the back carriage lock in such a way that during the last carriage movement the needles are pushed up 68 millimeters above the position of the operating needles. The needles are then returned to base position with their latches triggered. Only at this juncture can the heads come into operation and stitches be transferred.

It is an object of the present invention to provide a narrowing device of the type described, which can be fitted to normal parallel-bed knitting-machines.

It is another object of the present invention to provide a narrowing device of the type described, which is completely automatic and, once the narrowing program has been determined, using known programming systems, as, for example, a programming chain, will perform all the narrowing operations by itself.

Other objects and advantages of the invention will become apparent from the following description and accompanying drawings, in which:

FIGS. 1, 2 and 3 are the front, left and right-side elevational views, respectively, of a knitting-machine embodying this invention as a typical example of its application.

FIG. 4 is a view of the right head, formed by the mechanisms A and B, seen, without its protective covering, from the side of the left head, together with its actuating levers which are in turn controlled by co-axial, jointly operating cams.

FIG. 5 is a detail view of the mechanisms A and B.

FIG. 6 is a front view of the head in 'FIG. 5.

FIG. 7 corresponds to FIG. 6, with mechanism B removed.

FIG. 8 is a view of the head in FIG. 5 with mechanism B removed, seen from the opposite side to that in FIG. 5.

FIG. 9 is a view from below of the head of FIG. 7.

FIG. 10 is a sectional view taken substantially on the line A-B of FIG. 5.

'FIG. 11 is a view of the mechanism B in the position illustrated in FIG. 5 but seen from the opposite side to that in FIG. 5.

FIG. 12 is a view from below of mechanism B of FIG. 11.

FIG. 13 is a view of the pivotal punch, which is part of mechanism A and of a supporting element with guidechannels, illustrated more clearly later on.

FIG. 14 is a side view of a common knitting-machine needle with its latch in the triggered position.

FIG. 15 shows the three principal elevations of a transport needle for knitted fabric.

FIGS. 16, 17, 18, 19, 20, 21 and 22 show the various phases of a complete work cycle of the head illustrated in FIGS. 4, 5, 6, 7, 8, 9, 10, 11, 12 and 13 from the phase in which the head is lowered onto the needle-bed (FIG. 16) to the final phase ('FIG. 22).

FIG. 23 shows the phase in which the head, having now finished the narrowing operation, rises off the needle-bed and returns to rest in the original starting position whence it is to be lowered again (FIG. 16) to start the narrowing operation.

Referring now to FIGS. 1, 2 and 3 of the drawings, 1 and 2 refer to the two symmetrical heads relative to the center-line A-B. The heads are attached to a frame 3 which is free to pivot around a spindle 4 in such a 'Way that the heads can be lowered onto the needle-beds 5 at the same time adopting the operative position (FIGS. 16-22) or the rest position (FIG. 23). The numeral 6 refers to a tubular axis in which is housed a screw enabling the heads 1 and 2 to be symmetrically moved further apart or closer together. The numeral 7 refers to the drive shaft of the heads 1 and 2 which is driven by the electric motor 8. The numeral 9 refers to a tie-rod which enables the pivotal frame to be arrested at the desired angle. The numeral 10 refers to a handwheel which enables the positions of the heads 1 and 2 to be manually regulated. The numeral 11 refers to the carriage for the knitting-machine, 12 to the frame holding the needle-beds and the guides 13 of the carriage. The numeral 14 refers to the frame or base of the machine.

With reference to FIG. 4, it should be noted that the drawing must be so orientated that the center-line C-D is in a vertical position: the mechanisms A and B which comprise the heads will then be in the rest-position, with respect to the needle-beds, as is illustrated in FIG. 23. It should furthermore be noted that the point of convergence of the center-lines E-F and G-H, which, for reasons of space, cannot be shown on the same sheet as the figure, is, in practice, at the center of the pivotal axis 4 (viz. FIGS. 1, 2 and 3). The numeral 15 is the shaft bearing the various earns a which actuate the levers b (not all visible) which in turn rotate around the axis 16 and, with their .protruding noses, actuate, by means of tie-rods or levers,

the various components of mechanisms A and B. The numeral 17 refers to a dotted line which serves to indicate the outline of the lower part of the cover which conceals the various parts and which is clearly seen in FIGS. 1, 2 and 3. In brief, the function of FIG. 4 is to show the device in a typical embodiment.

With reference to FIG. 5, it should be noted that it is well to have a preliminary look at FIGS. 8 and 11 which show the mechanisms A and B separately. The special feature of the head is indeed the fact that mechanism B can only function in conjunction with mechanism A, while the latter is to some extent independent of B. When both mechanisms are working together they enable one to narrow on both forward and rear needle-beds, whereas mechanism A by itself admits of narrowing on the rear needlebed only.

This said, and still with reference to FIG. 5, 18 refers to an element which actuates the butt 19 (viz. FIG. 14) of the normal knitting-machine needles located in the rear needle-bed. The element pushers, or better, pulls on the needle (or needles) causing it to slide in its groove. The elementwill be termed lifter. Again with reference to FIG. 5, 20 refers to a species of prismatic slide running in a special guide-channel of corresponding shape in the metal block 21. The slide 20 is actuated through the tie rod 22 by the one of levers b moved by the earns a. The numeral 23 refers to a sort of chisel with the opposite function of the lifter 18. At the appropriate moment it presses down the needle raised by the lifter, again by bearing on the needle butt. This chisel, which will be termed pusher, is hinged by means of a pin 24 into a base 25 fixed to the end of the slide-bar 26 running inside the sleeve-guide 27 which pivots on the pin 28. The numeral 29 refers to a coil-spring which bears on the pusher 23. The numeral 30 refers to a lever to the end of which is attached the pin 31 which bears on the pusher 23 to make it pivot on the pin 24, thus compressing the return spring 29. The lever 30, which reaally acts as a rockerarm, is actuated by the tie-rod 32 (FIG. 8). The numeral 33 (still in FIG. 5) refers to the punch, seen in greater detail in FIG. 13, which pivots on the pin 34 and is acted upon by the spring 35.

The needles c of the punch marry, at a certain stage of the operation, as will be seen later, with the element 36 (viz. FIG. 13) which is provided with grooves d which serve as guides for the needles themselves. To sum up, since the pusher 23 and the punch 3-3 are attached to the same base 25 they rise and fall together.

Furthermore, since the pusher is acted upon by the spring 29 and the pin 31 it can pivot on the pin 24. The punch, on the other hand, as well as rising and falling can pivot on the pin 34, being acted upon by the spring 35 and the needle-guide element 36, which latter forms an integral part of the frame of the head and thus remains fixed in relation to the punch.

Again with reference to FIG. 5, 37 refers to the needle aligner, which is formed out of a blade of spring steel, the shape of which is better visible in FIGS. 6 and 10. The aligner is attached by means of the plate 38 to the slide 39 which runs in a special guide-channel in the block 21. This slide is actuated by a lever, or rocker-arm, 40, operated in turn by the tie-rod 41. The numeral 42 refers to an element which, at the end of the transfer cycle, lowers the needles, again acting on the needle butts, and strikes them back into the needle-bed in the inoperative position. The element 42 is attached to the slide 43 which is also slidably mounted in the block 21 and is actuated by means of its own tie-rod.

The components of mechanism A are also visible in FIGS. 6, 7, 8, 9, 10 and 13.

With reference to these last figure, 44 refers generally to the housing of the head or also to an integral part of it. In FIG. 7, 45 refers to the fixed arm which supports and houses the bed 46 of the block 36 containing the guidegrooves of the punch needles. The numeral 47 (again with reference to FIG. 7) refers to a cylinder attached to the lever 48 which enables the sleeve 27 (viz. also FIG. 5) to be rocked, where, again in FIG. 5, 49 refers to the tie-rod of the lever 48. The numeral 50, 51, 52 and 53 refer to the levers which, in FIG. 4 come under the generic heading b and which actuate the cylindrical slide bar 26, the tierod 41 of the slide 39, the tie-rod 22 of the slide 20 and the tie rod 32 which acts on the pusher 23, respectively. The numeral 54 refers to the shaft bearing the earns a which actuate the levers 50, 51, 52 and 53 while 55 refers to a toothed wheel mounted on the shaft 54. The letter 2 refers to the upper front section of the lower casing, which is fiat and serves for the mounting of the mechanism B.

Having thus described mechanism A we shall now pass to mechanism B with particular reference to FIGS. 6, 11 and 12.

Mechanism B consists of a mounting plate 56 which acts as a species of base-plate and is fixed to the flat part 2 (FIG. 7) of the head casing. All the various components of mechanism B are joined directly or indirectly to the plate 56 by means of the upper and lower supports, 57 and 58, respectively. The numerals 59, 60, 61 and '62 (FIG. 11) refer to the four sides of an articulated parallelogram. Side 62 has a protruding end 1 which forms an arm to which is hinged the extension '63. The side has a protruding end g hinged to support 58 by means of a pin 64. The numerals 65 and 66 refer to two tubular elements in each of which is housed a return coil-spring, of which only one, 67 (FIG. 11), is visible. Each tubular body functions as a slide-guide by means of a slot, of which only one, 68 (FIG. 11), is visible, and of a species of slide which will be more amply described later on. The tubular element 66 is joined to side 60 of the articulated parallelogram at one end by means of the connecting-rod 69, and at the other end by means of the variable-length, telescopic connecting-rod 70. The tubular element 65, on the other hand, is fixed to the element 71, which is an integral part of plate 56. The numeral 72 (viz. FIG. 12 in particular) refers to two coil-springs which tend to hold the parallelogram in a compressed position. The numeral 73 refers to an arm attached protrudingly to the extended portion of side 60 of the articulated parallelogram and then attached to arm 74, which forms an integral part of support 58, by means of a bolt 75, which compresses a coil-spring and thus constitutes an elastic joint designed to cushion shocks. The numeral 76 refers to a specially shaped plate, the function of which is to rest on the inoperative needles during the phases of work and thus to act as a species of stop control to prevent the needle-bed from swinging down (viz. FIG. 17). In other words, when the head is lowered onto the needle-beds (viz. FIG. 16) the shaped plate comes into contact with the butts of the needles, 19, and forces the articulated parallelogram to open in accordance with the scheme illustrated by FIGS. 17, 18, 19, 20, 21 and 22, dependent on the particular phase of work.

The slide attached to the tubular body 66 is formed by an element 77 which has the function of striking the needle butt and pushing it up. The element 77 is attached to the slide 78 which in turn is joined to the tube 66, which acts as a slide-gude for it. The element 77 is hinged in such a way as to be tiltable upwards. The numeral 79 refers to a spring which bears down on the. element 77 and holds it in normal position (viz. also FIG. 16). The numeral 80 (FIG. 12 in particular) refers to the sledgeslide mounted on the tubular body '65 which serves the purpose of pressing down the needle butts after the stitch, or stitches, have been transferred and the needles have to be returned to the inoperative position. The slide 80 is actuated by the pin 81 which forms an integral part of the tow-element 63. The pin 81 is in contact with the slide-bar 82 which is fixed above the slide 80 in such a way as to be able to drag it (viz. also FIGS. 16, 23).

It should be noted that, while the slide 73 presses on the needles, the slide 80 serves the purpose of pressing them down after they have been borne up. For this reason the slide 80 is in the form of a sledge which, while remaining in contact with the needle butt, is able to pass below the element 77 thereby tilting it upwards, which upwards-tilting enables the slide 80 to continue its stroke until it strikes the needle back into the inoperative position.

The tubular body 65 which forms an integral part of the plate 56 is inclined with respect to the latter (viz. FIG. in such a way that when the head is lowered onto the needle-beds the aforesaid body is almost parallel to the forward needle-bed (viz. FIGS. 17, 18 and 19).

The mechanism B is actuated by the movement of the head towards the needle-beds. This lowering action causes the slide 78 to rise (viz. FIGS. 16 and 17), thus creating tension in the springs inside 66 and the spring 72. Furthermore, it causes the deformation of the articulated parallelogram.

In other words, mechanism B, chiefly by means of the articulated parallelogram, allows for the transformation of the head and of mechanism A, in such a way that, while the head is lowered, slide 78 is compelled to run up, and, at a certain moment, slide 80 is compelled to run down. The down-stroke of slide 80 is achieved by means of the lever 83, which is actuated by means of the protrusion 84 (viz. FIG. 5) of one of the levers b (FIG. 4).

Before continuing it is well to consider the nature and differences of the needles illustrated in FIGS. 14 and 15, wherein: h refers to the hook; i refers to the triggered latch; 85 refers to the spring of the transfer needle, underneath which, during the transfer operation, the upper part of the common needle (FIG. 14) has to be inserted. The letters m and n refer to the hook and the triggered latch of the transfer needle.

We now propose to explain the working of the coupled mechanisms A and B.

As each head is equipped with mechanisms A and B, and as the two heads are symmetrical and symmetrically mounted on the knitting-machine (FIG. 1), the working of the mechanisms A and B will be illustrated by describing the functioning of a knitting-machine embodying the invention. As soon as it becomes necessary to narrow a given knitted fabric the carriage of the knitting-machine 6 stops at the end of its stroke to the left and the heads are lowered automatically onto the needle-beds. It should be noted that the carriage, being furnished with shaped locking devices, keeps the latches of the needles in the triggered position.

The heads then perform the work-phases illustrated in FIGS. 1622. "First the two mechanism B enter into operation, and then the two mechanisms A. Each mechanism B has the function of raising the transfer needles (as has already been stated, they may be one, two or three in number). The mechanisms A then raise the needles (one, two or three) with the lifter 18 and insert them underneath the springs of the corresponding transfer needle. At the same time, the mechanisms B lower the transfer needles, previously raised, under the springs of which the. common needles raised by A are inserted. The transfer needles then drop the stitches onto the common needles which had been inserted underneath them. At this point the two punches 33 are lowered, and enter into operation together with the pusher 23. The common needles are thus lowered, accompanied by the punches. On the completion of this movement the punches pick up the stitches and pivot slightly with the stitches hooked on. Now the automatic mechanism comes into operation, shifting the head towards the center of the machine by one, two or three needle-spaces, depending on the program. On the completion of this lateral shift the punches pivot in opposite directions and carry the stitches inwards onto the adjacent needles, that is to say, in the directions in which the knitted fabric has to be narrowed. The two lowering elements 42 come into play as soon as the punches have dropped the stitches onto the new needles, and serve the purpose of returning the redundant needles to the inoperative position.

The operations are automatic and continue cyclically until the predetermined program has been completed, this corresponding to the symmetrical edges of the knitted fabric it is wished to manufacture.

When the program has been completed the two heads rise simultaneously, detaching themselves from the needlebeds, to adopt the rest-position until such time as a new length of knitted fabric is started, or further narrowing operations are required to be performed on the same length of fabric.

As has already been stated, the mechanisms A and B enable narrowing to be performed on both needle-beds, and permit the manufacture of double-jersey knitted fabric with reduction of the number of needles knitting; when mechanisms B are removed, however, the machine can produce single-knit jersey fabrics.

FIGS. 16-23 illustrate in detail the movements of the needles and of the mechanisms A and B.

FIG. 16 shows the first phase. that is to say, the arrival of the right head onto the needle-beds, that is, the all but final downwards pivoting on shaft 4. The specially-shaped plate 76 is about to come into contact with the butts 19 of the trnasfer needles in operative position, while the pusher element 77 is about to take u its position behind the butt 19 of the transfer needle 86 prior to pushing it up. The slide 78 is about to be pushed up by the element 63 as soon as the deformation of the articulated parallelogram starts, a deformation which reaches its peak when the guide-element 65 is parallel to the forward needle-bed 5b.

Comparison of the FIGS. 16 and 17 shows clearly the deformation to which the articulated parallelogram is subjected, and the end of the up-stroke of the pusher 77 and of the needle 86 (of which there may be two or three). As has already been said, the element 63 acts on the slide 78 by means of the slide-bar 82.

In the phases illustrated in FIGS. 16 and 17 mechanism A does not undergo any internal movement; it merely assumes the position (FIG. 17) in which it is ready to intervene.

FIG. 18 shows the third phase. The lifter 18 starts pushing up the common knitting-machine needle (of which there may be two or three) by means of the butt. The hook of the needle is then inserted underneath the spring 85 of the transfer needle.

FIG. 19 shows the fourth phase of the cycle. The transfer needle is carried down by the slide 80, which, being sledge-shaped, is able to pass underneath the element 77, tilting the element as it does so. The needle 87, which has so far kept the stitch it lifted off needle 86, continues its stroke upwards under the action of the lifter 18, until its hook reaches a position in which it is engaged by a needle of the punch 33.

At this point, the fifth phase, illustrated by FIG. 20, begins. The pusher 23, still acting upon the butt, pushes down the needle 87 which in this movement is accompanied by the punch 33.

FIG. 21 shows the sixth phase, in which the punch 33, with the stitch already hooked on (or with two or three stitches, if there are two or three needles 87 in operation), drops the needle (or needles), which movement is assisted by the guides d (FIG. 13). At this point, it should be noted that the heads sliding laterally on the shaft 6 move closer together by one needle-space (or by two or three needle-spaces).

FIG. 22 shows the phase in which the punch 33, now having been displaced to a position parallel to the needlebeds, slips the stitch (or stitches) on the adjacent needle (or needles) 87 onto that (or those) with which the first phase, as illustrated by FIG. 16, started. This latter phase is the final transfer phase proper. When this phase has been completed, the head rises (still coupled to the other symmetrical head) and, pivoting around the axis 4, follows a curved trajectory to take up the position of rest (FIG. 23), in which position it remains ready to carry out the subsequent narrowing operation as dictated by the program.

In the final phases of work (FIGS. 21 and 22), in which the heads move towards the center of the machine, the aligning element 37 has had the function of aligning the butts of the adjacent needles towards the center of the machine itself, so that they are ready for another transfer cycle. The element 42 (viz. FIG. 20, for example) has the function of pressing down the needle (or needles), which has (have) given up the stitch, and of returning it (them) to the inoperative or rest position.

All the movements of the mechanisms A and B are synchronized by the various cams a, one for each arm b (viz. FIG. 4). Both arms and tie-rods must be perfectly adjustable. The shape of the cams admits of perfectly synchronized movements, in-so-much as the cams form an integral unit, being mounted on a single shaft 15.

The slides 78 and 80 are returned to their rest positions (FIG. 12) by the springs housed inside the tubular bars or guides, 65 and 66.

While the slide 78 is actuated directly by the deformations of the articulated parallelogram, through the agency of the element 63, the slide 80 is actuated by the lever 83, moved in turn by the protruding end of an arm b. During the stroke, that is, the work-stroke of the slides, the springs are compressed and their elasticity is utilized to return the slides to the restor starting position (FIG. 12), ready to begin another work cycle.

At this point, what has already been stated for mechanism A may be repeated for mechanisms B. The example illustrated is only an indication, as it will be realized that the parallelogram can be constructed in extremely different ways. The tubular elements 65 and 66 are really guidebars which, amongst other things, house the return springs. Although mechanism B can only operate when coupled to A, it comes into operation before A at the moment when the head is lowered. Mechanism A is actuated by this lowering movement, which causes the deformation of the articulated parallelogram, by one of the cams a, through the agency of one of the levers b and the lever 83, which transmits and multiplies the movements, and, finally, by the return-springs housed in the guide-bars 65 and 66.

The two heads, as has been stated, are symmetrical; thus while, for example, the aligning element 37 of FIG. 5, which corresponds to the head 2 (FIG. 1), is turned towards the center-line A-B, that is, towards the left, the one corresponding to head 1 is turned towards the right, as is true in the case of many other elements, which truth being obvious if the previous descriptions have been understood.

The movement of the heads 1 and 2 towards the center of the machine (center-line A-B, viz. FIG. 1) must be perfectly synchronized with the movements of the mechanisms A and B. Since the movements of the heads are simple linear displacements, each point of displacement corresponding to one, two or three needle-spaces, it is obvious that the mechanisms required to achieve such movements present no mechanical design difficulty and may thus be fashioned as is thought fit.

It will thus be seen that the objects of this invention have been fully and effectively accomplished. It will be realized, however, that the foregoing specific embodiments have been shown and described only for the purpose of illustrating the principles of this invention and are subject to extensive change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.

We claim:

1. In a device for automatic narrowing on both needlebeds of a flat knitting-machine, the combination compris ing: two heads mounted on a frame, said frame being mounted on the knitting-machine adapted to lower said heads in contact with the needle-beds to assume an operative position, and adapted to raise said heads to a certain distance to assume a rest-position, mechanical means for allowing said heads to be drawn closer together with a slip-stick motion, each interval of said slip-stick motion corresponding to at least one needle-space, said slip-stick motion occurring whenever said heads are about to transfer to the adjacent needles the stitches previously taken up, means for actuating the butts of said needles with said heads; a first mechanism combined with a second mechanism, both said mechanisms substantially comprising the said heads, said second mechanism for effecting narrowing on the forward needle-bed of the said needle beds, said forward needle-bed being furnished solely with transfer needles, said first mechanism adapted to narrowing only on the rear needle-bed of the said needle-beds, said rear needle-bed being furnished solely with normal needles, said second mechanism being independent of said first mechanism but functioning in conjunction therewith a lifting element, a needle-aligning element and a lowering element, said lifting, needle aligning and lowering elements substantially comprising the said first mechanism, said lowering element adapted to render said needles inoperative at the end of each narrowing operation, the said elements acting upon said needles solely by means of the butts of said needles, slides for mounting said elements, a base in combination with said slides, guides for slideably receiving said slides, a pushing element attached to said base for pushing the needles down, a punch for taking up the stitches to be transferred for the purpose of narrowing, said pushing element and said punch being pivotal, with respect to said base, spring means for actuating the pushing element, a base attached to said bar being slidable within a support, said support being pivotally mounted about a pin, an operating assembly comprising cams, levers and tie-rods for transmitting movement to said individual elements; two further slides, said slides substantially comprising the second mechanism, one of said further slides adapted to carry up the transfer needle, the other of said further slides adapted to carry down said transfer needle, two additional guides attached to said two further slides, one of said further slides being actuated by parallel motion means, said parallel motion means being deformed when said heads are lowered onto said needle-beds, a lever for actuating the other of said further slides, a cam for controlling said lever, the said further slides comprising a lifting slide and a lowering slide, wherein the operation of the further slides is carried out in contraposition in such manner that, as soon as the said lifting slide reaches the end of its up-stroke, the said lowering slide comes into action, said lowering slide starting from the upper end-of-stroke position and carrying the needles down into the rest-position, said lifting and lowering slides being returned to the rest-position by spring members as soon as the said head rises into the rest-position, all the movements of said needles being actuated by means of the butts of said needles.

2. The structure defined in claim 1, wherein the first mechanism comprises the said punch, said punch having needles working in conjunction with a grooved element, said grooved element being an integral part of the frame of the head and supporting and guiding the said needles of said punch by means of said grooves at determined phases of the movement of said punch.

3. The structure defined in claim 1, wherein the said lifting slide which carries up the transfer needles is provided with a small pusher, said pusher bearing upon the transfer needles and actuating said transfer needles by means of the butts of said needles and being held in normal position by a spring and being tiltable upwards by the said lowering slide, an additional slide coupled to said pusher, said additional slide being very low and in the shape of a sledge, said additional slide being constructed so as to strike said same needle-butt as is acted upon by said pusher and capable of pushing down said needle and of sliding underneath said pusher, said pusher being thereby tilted up.

4. The structure defined in claim 3, wherein: the pushing element of said first mechanism is pivotally mounted about a pin, the pivotal movement of said pushing element being independent of the base pushing element; said pusher is furthermore, pivotally mounted about a second pin of the support, the said support housing the slidable bar, said bar being attached at its lower end to the said base; the pivotal movements of the punch being spring actuated, by the pivotal movements of said support about said pin and by the butter action of an opposed guideelement.

References Cited UNITED STATES PATENTS 575,395 1/1897 Granz 66-70 1,120,332 12/1914 Peters 66-70 1,294,839 2/1919 Schwab 66-96 3,248,903 5/1966 Coppo 6670 MERVIN STEIN, Primary Examiner 

